JPH0823268B2 - Open shield method and concrete box used for it - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an open shield method for constructing underground structures such as underground passages such as water and sewage systems, common ditches, telegraphs, telephones and the like in an urban area, and a concrete box used therefor.

[0002]

2. Description of the Related Art The open shield construction method is a highly rational construction method that takes advantage of the advantages of the open cut construction method (open cut construction method) and the shield construction method. FIG. 4 shows its outline. In the figure, reference numeral 1 denotes an open shield machine, which has a front surface composed of left and right side wall plates 1a and a bottom plate 1b connected to these side wall plates 1a,
It is a shield machine with openings on the back and top. The open shield machine 1 is formed with the tip ends of the side wall plate 1a and the bottom plate 1b as blade openings, and the propulsion jacks 2 are arranged vertically rearward near the center or the rear end of the side wall plate 1a.

Although not shown, the open shield machine 1 is installed in the starting pit, the propulsion jack 2 of the shield machine 1 is extended, and a reaction force is applied to the reaction wall in the starting pit to advance the shield machine 1. Then, the first concrete box 4 forming the underground structure is suspended from above and set behind the propulsion jack 2 which is contracted in the tail portion 1c of the shield machine 1. Struts are arranged between the propulsion jack 2 and the reaction wall to adjust the distance as appropriate. In addition, the start pit is composed of a retaining wall, and in order to start the open shield machine 1, a part of this retaining wall is cut off with a mirror. However, if necessary, ground improvement is applied to the front part of the starting pit by injecting a chemical solution or the like. Sometimes I leave it.

An excavator 9 such as a shovel excavates and discharges earth and sand from the front surface or the upper surface of the open shield machine 1. Simultaneously with or after this soil discharging step, the propulsion jack 2 is extended to advance the shield machine 1. For this forward step,
In front of the concrete box 4, a pushing angle 8 made of a frame body made of box steel or shaped steel is provided. Then, the second concrete box 4 is suspended in front of the first concrete box 4 in the tail portion 1c of the shield machine 1. Hereinafter, the same soil discharging step, advancing step, and setting step of the concrete box 4 are appropriately repeated to sequentially leave the concrete box 4 in the ground in a row along with the forward movement of the open shield machine 1, and further to this concrete box. Backfilling 5 is applied to the upper surface of 4.

The concrete box 4 is shielded by the shield machine 1
When suspending in the tail portion 1c of, the height adjusting material 7 such as a concrete block is arranged below the concrete box 4, and in the tail portion 1c, in the voids on the left and right sides and the lower portion of the concrete box 4. The grout material 6 is filled.

In this way, when the open shield machine 1 reaches the reaching pit, it is removed and the construction is completed.

In the open shield construction method as described above, the concrete box 4 is suspended in the tail portion of the shield machine 1 as described above, and exits from the tail portion 1c as the open shield machine 1 advances and remains in the ground. It is something that goes. The concrete box 4 is made of reinforced concrete, and includes a left side plate 4a, a right side plate 4b, an upper floor plate 4c and a lower floor plate 4d, as shown in FIG.
The front and rear surfaces are open as openings 10.

By the way, by the open shield construction method as described above, the concrete box 4 has the tail portion 1 of the shield machine 1.
It is necessary to connect to the concrete box 4 already installed when it is hung in c. This concrete box 4
As a method for connecting them, a box culvert joint as disclosed in Japanese Utility Model Laid-Open No. 49-45110 can be used.

The details are shown in FIG. 6, where 11 is a bolt hole in each corner of the concrete case 4 in the direction perpendicular to the end face 12 of the concrete case 4 and the total length of the bolt 13. Is provided in a predetermined length capable of storing Reference numeral 14 denotes a groove that opens inside the concrete box 4 and that is connected to the bolt hole 11 and that is provided at an intermediate position that divides the length of the bolt hole 11 into two equal parts and is substantially perpendicular to the bolt hole 11.

In this way, the bolt 13 is stored in the bolt hole 11 of the concrete box 4 as shown by the chain line in FIG. 6 until it is hung down in the tail portion 1c of the shield machine 1, and the concrete box is When connecting 4 to each other,
The bolt 13 is pulled out from the bolt hole 11 in the direction of the arrow, inserted into the bolt hole 11 of the opposing concrete box 4, and the tip of the bolt 13 is pulled out to the groove 14 provided in the opposing concrete box 4. Thereafter, the nuts 15 are screwed into the two ends of the bolts 13 from the grooves 14 of the concrete box 4 and tightened. By performing such work on the four corners of each concrete box 4, the connection work between the concrete boxes 4 is completed.

[0011]

With such a joint alone, it is simple to connect each of the four corners of the concrete box 4 with the thin bolts 13, and it is difficult to make a rigid connection. In particular, when performing a curved construction, the stroke of the propulsion jacks 2 arranged on the left and right inside the shield machine 1 is made to be different and the shield machine 1 is bent and moved forward, and the concrete box 4 is also uneven on the left and right. Since the load is applied, it is impossible to prevent the concrete boxes 4 from shifting from each other.

When a force is applied by the propulsion jack 2 for advancing the shield machine 1, the left and right side walls 4a, 4b of the concrete box 4 are compressed and the upper floor plate 4c and the lower floor plate are compressed. A bending moment may be applied to 4d, and a crack may occur on the end face thereof.

The object of the present invention is to eliminate the disadvantages of the above-mentioned conventional example, to prevent the occurrence of cracks on the end faces of the upper and lower floor plates of the concrete box when receiving the propulsive force of the jack, and to prevent the concrete box from interchanging with each other. Can be easily rigidly joined to withstand joint displacement during curve construction, and part of the members can be diverted to save costs, and an open shield construction method that also prevents split fracture of concrete boxes It is to provide the concrete box used for it.

[0014]

In order to achieve the above-mentioned object, the present invention has a propulsion jack provided inside the left and right side wall plates,
A step of excavating and discharging earth and sand in front of the front or upper surface opening of the open shield machine having the front, rear surface and upper surface opened,
The process of extending the propulsion jack and making the concrete box a reaction force to advance the shield machine, and the process of suspending and setting a new concrete box from above behind the propulsion jack that has been compressed in the tail part of the shield machine. In the open shield method of sequentially burying concrete boxes in a vertical line by repeating the above, the concrete box for underground structures is composed of left and right side plates, upper floor plate and lower floor plate, and the front and rear end faces with the opening face in the center are joint faces. The body has a large horizontal width, screw holes are provided in the thickness direction, and a steel plate for embedding with a plurality of stud dowels projecting on the back side is aligned with the front and rear end faces of the concrete box, and the surface is It is embedded in the upper floor plate and the lower floor plate so as to be exposed, and the inner steel plates of the upper floor plate and the lower floor plate are covered with this burying steel plate. Is abutting the ends of the steel plates for burying, a steel plate for joining with a screw hole so as to straddle the steel plates for burying is applied, and the steel plate for burying and the steel plate for joining are bolted and joined. The main point is to do.

[0015]

As described above, when the force of the propulsion jack for advancing the shield machine is applied, the left and right side walls of the concrete box are compressed and bending moment is applied to the upper floor plate and the lower floor plate. Although there is a risk that cracks will occur at the end face thereof, according to the present invention, the burying steel plate is a steel plate having a large horizontal width as attached so as to cover the inner surface of the upper floor plate and the lower floor plate of the concrete box. Since the inner surface of the concrete box in which the burying steel plate is buried is protected and covered by this steel plate, the rigidity is increased by this steel plate, and even if a load for pushing out by the propulsion jack is applied to the side of the opening surface. It is possible to prevent the occurrence of cracks and the application of corners. Further, since a plurality of stat dowels are provided on the back side of the burying steel plate, the burying steel plate and the concrete box are strongly bonded.

In the concrete box, the ends of the steel plates for embedding are abutted against each other, and a steel plate for joining is provided with a screw hole so as to straddle the steel plates for embedding. The steel plates are joined together by bolts, and the steel plates are joined together to form a rigid connection, which can prevent misalignment during curve construction. Also, after construction,
Since the bolts can be removed from the steel plate for joining and diverted, the work cost can be reduced. Moreover, since the concrete boxes are connected to each other only by bolting the steel plate for burying and the steel plate for joining, the concrete boxes can be easily joined and the joining work can be performed quickly.

[0017]

Embodiments of the present invention will now be described in detail with reference to the drawings. First, the concrete box of the present invention will be described. This concrete box 4 is made of reinforced concrete, and comprises a left side plate 4a, a right side plate 4b, an upper floor plate 4c and a lower floor plate 4d as shown in FIG. The front and rear surfaces form the opening 10.

As shown in FIGS. 1 to 3, according to the present invention, the concrete floor box 4 has an upper floor plate 4c and a lower floor plate 4d.
A steel plate for embedding 16 having a plurality of stat dowels 17 projecting at appropriate intervals on the back side is aligned with the front and rear end faces of the concrete box 4 and the upper floor plate 4c is exposed so that the surface is exposed.
And embedded in the lower floor plate 4d.

The burying steel plate 16 has such a large width that it can be mounted so as to cover the upper floor plate 4c and the lower floor plate 4d from the inside at the front end and the rear end of the concrete box 4. Also, screw holes 18 are provided in the surface in the thickness direction at appropriate intervals.

As described above, the burying steel plate 16 is composed of the upper floor plate 4c and the lower floor plate 4d at the front end and the rear end of the concrete box 4.
Can be attached so as to cover from inside, but when the concrete box 4 is manufactured, it can be placed in a concrete form and attached by simultaneous molding during concrete pouring.

Next, the concrete box 4 of the present invention will be described.
I will explain the open shield method using
Although an outline of the entire construction method is shown in FIG. 4 and detailed description thereof is omitted, the excavation by the open shield machine 1 and the setting process of the concrete box 4 are repeated to sequentially open the concrete box 4 in the open shield machine 1. With the forward movement of the concrete box, it is left in the column in the ground, and backfilling 5 is applied to the upper surface of the concrete box 4.

In this case, the concrete box 4 to be hung inside the shield machine 1 and the concrete box 4 previously installed in the shield machine 1 are screw holes 19 so as to straddle the steel plates 16 for burying. The joining steel plate 20 provided with is applied, and screw holes 18 for fitting the burying steel plate 16 and the joining steel plate 20 to each other,
Insert bolt 21 into 19 and fix it with bolts.

As described above, the concrete box 4 receives a reaction force when the propelling jack 3 is extended to advance the shield machine 1, but the front and rear end faces of the concrete box 4 and the upper and lower floor plates 4c and the lower floor plate. The inside of 4d is covered with a steel plate 16 for burying, the rigidity is increased by the steel plate 16 to form a high-strength portion, and the ends of the steel plate 16 for burying abut against each other. Even if a considerable load is applied to the front end of the, the corners of the inner part do not hang or cracks occur due to splitting. This is also the case when performing a curve construction, and the strokes of the propulsion jacks 2 arranged on the left and right inside the shield machine 1 are made different and the shield machine 1 is bent and moved forward. The load is unevenly distributed in the area, but it is possible to prevent cracking and cracking.

Further, when the curve construction is completed, such a rigid joint between the burying steel plate 16 and the joining steel plate 20 becomes unnecessary, so the bolt 21 is removed and the joining steel plate 20 is removed.
Can be diverted to the connection with the burying steel plate 16 at another place.

It is also possible to jointly join the concrete box 4 with the bolts 13 shown in FIG.

[0026]

As described above, the open shield construction method of the present invention and the concrete box used for the same can prevent the end faces of the upper and lower floor plates of the concrete box from being cracked when receiving the propulsive force of the jack. You can
Furthermore, the concrete boxes can be easily and rigidly joined together to prevent misalignment during curve construction, and part of the members can be diverted to save costs and prevent the splitting of concrete boxes. It will also be.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional front view showing one embodiment of a concrete box of the present invention.

FIG. 2 is a vertical sectional front view showing one embodiment of the concrete box of the present invention.

FIG. 3 is a cross-sectional plan view showing one embodiment of the concrete box of the present invention.

FIG. 4 is a vertical sectional side view showing an outline of an open shield construction method.

FIG. 5 is a perspective view showing a conventional example of a concrete box.

FIG. 6 is a vertical cross-sectional side view showing joining of conventional concrete boxes.

[Explanation of symbols]

1 ... Open shield machine 1a ... Side wall plate 1b ... Bottom plate 1c ... Tail part 2 ... Propulsion jack 3 ... Partition wall 4 ... Concrete box 4a ... Left side plate 4b ... Right side plate 4c ... Upper floor plate 4d ... Lower floor plate 5 ... Backfilling 6 ... Grout material 7 ... Height adjusting material 8 ... Push angle 9 ... Excavator 10 ... Opening 11 ... Bolt hole 12 ... End face 13 ... Bolt 14 ... Groove 15 ... Nut 16 ... Buried steel plate 17 ... Stat dowel 18 ... Screw hole 19 ... Screw Hole 20 ... Steel for joining 21 ... Bolt

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display location E21D 11/08 F16L 1/038 (71) Applicant 594074805 Toei Concrete Industry Co., Ltd. Fukami, Yamagata City, Yamagata Prefecture No. 19 (71) Applicant 000116769 Asahi Concrete Industry Co., Ltd. 1-2-2 Tsukiji, Chuo-ku, Tokyo (71) Applicant 593012402 Sumitomo Concrete Co., Ltd. 4 (71) 13-Arakicho, Shinjuku-ku, Tokyo Applicant 000112196 3-4, Marunouchi, Chiyoda-ku, Tokyo (72) Inventor Masahiro Nakai 3-4-1 Marunouchi, Chiyoda-ku, Tokyo Tokyo (72) Inventor, Uemura Makoto Tokyo 1-2-7-14 Fujimoto, Kokubunji City Uemura Giken Kogyo Co., Ltd. (72) Inventor Tokizo Saita 13-Arakicho, Shinjuku-ku, Tokyo In Juken Concrete Co., Ltd. (72) Inventor Takuya Arimatsu 13-2 Araki-cho, Shinjuku-ku, Tokyo In Kenken Concrete Co., Ltd. (72) Inventor, Seto Someya 1-8-2 Tsukiji, Chuo-ku, Tokyo Asahi Concrete Industry Co., Ltd. (72) Inventor Hiroyuki Nitta 19 Tomijindai, Yamagata City, Yamagata Prefecture Toei Concrete Industry Co., Ltd. (72) Inventor Keisuke Kawahara Shingu, Kasuya-gun, Fukuoka Prefecture Kyukon Co., Ltd. (72) Inventor Makoto Note 1092 Yokoshiba, Yokoshiba-cho, Yamatake-gun, Chiba Prefecture Chiba Ceramics Co., Ltd. (72) Inventor Hisashi Ito 1-6-3 Kandaogawacho, Chiyoda-ku, Tokyo Kawashin Building Koken Sangyo Co., Ltd. (56 ) References JP-A-52-25430 (JP, A) JP-B-48-11617 (JP, B1)

Claims (2)

[Claims] 1. A process of arranging propulsion jacks inside left and right side wall plates, excavating and discharging earth and sand from the front or top opening of an open shield machine having front, rear and top openings, and extending the propulsion jack. Repeat the process of moving the shield machine forward by using the concrete box as a reaction force and the step of suspending and setting a new concrete box from the top behind the propulsion jack that was contracted in the tail part of the shield machine. In the open shield method of sequentially burying concrete boxes in vertical columns, the concrete box for underground structures that consists of left and right side plates, upper floor plate and lower floor plate, and the front and rear end faces with the opening face in the center is the joint surface A steel plate for embedding, which has a large width, is provided with screw holes in the thickness direction, and a plurality of stud dowels is projected on the back side, and its ends are attached to the front and rear end faces of the concrete box. Aligned, and embedded in the upper floor plate and the lower floor plate so that the surface is exposed, the inner steel surface of the upper floor plate and the lower floor plate is covered with this burying steel plate, the concrete box to be connected to each other, The ends of the steel plates for embedding are abutted against each other, and the steel plates for joining provided with screw holes so as to straddle the steel plates for embedding are applied, and the steel plates for embedding and the steel plates for joining are bolted and joined. An open shield construction method characterized by. 2. A left and right side plate, an upper floor plate and a lower floor plate,
For a concrete box for underground structures that has front and rear end faces that have an opening in the center and has a large width, has screw holes in the thickness direction, and has multiple stat dowels protruding on the back side for embedding Steel plates, the ends of which are aligned with the front and rear end faces of the concrete box, and are embedded in the upper floor plate and the lower floor plate so that the surfaces are exposed, and the inner surface of the upper floor plate and the lower floor plate is covered with this embedding steel plate. The concrete box used for the open shield method characterized by the above.